Comments on: Analog TV era ends, DTV begins, complexity thrives
Across the USA at midnight, the era of analog broadcast television ended. It lasted more than 60 years. Quite an achievement for any technology.
I must admit, I have mixed feelings about this "advance" in technology.
A bit nostalgic
Sure, I'm somewhat nostalgic about the television business. I began working in TV at the age of 13, when I saw an announcement on a local PBS station (KEET 13), asking for volunteers. I rode my bicycle (because I was too young to drive) down to the TV station, and told the general manager, Don Telford, an older gentleman in his 60's, that I would like to work at the station.
The manager looked at me over his eyeglasses, asked a few questions, then took a huge risk: he made me a "switcher" -- the person who runs the master control that puts programs on the air. He was a trusting man.
It was a great job, and I loved doing it. After two weeks, he called me back into his office. "You are no longer a volunteer, " he said. "We are hiring you as an employee to run the master console every day."
Two years later, at the age of 14, with the PBS experience as leverage, I managed to get a job at the ABC network station as a cameraman and film developer. And, thus began a passion for TV, including every facet of the business... from live news production, commercial production, film, video, engineering... I could not learn fast enough every job and opportunity at the station.
A few years later, when I finally left to attend the university, I had worked my way up to the top production position at the station: director of the 6PM news, a live production that required fantastic concentration and timing.
Understandable, therefore fixable
One of the things I liked about those days is that you could learn, understand, participate, and contribute to every aspect of the technology and art.
For example, when I was 14, working at PBS, the stations main color TV camera (large complex devices back then) stopped working, and had been pushed into the corner. The engineers told me something major was wrong, and it could not be fixed.
Never being one to be discouraged, I worked on the camera during the less busy times of running the master console. Alone, using an oscilloscope, I worked on the camera for a several weeks, tracing the signals through the various subcomponents of its video circuitry. I finally discovered that the primary drive transistor for its cathode (the source of electrons for the beam that captures the image) was burnt out. A quick replacement, fixed the camera, and the station manager was delighted to have the color camera back on the air. (Rather than black and white).
Anyway, I have a point here, beyond just the story. My point is, the technology, even in it's more complex domains (inside a TV camera) was understandable and workable. It wasn't beyond our grasp, as even demonstrated by a 14 year old boy.
The same is not true for DTV. The modern digital world consists of several higher level components built on lower level technologies that are, frankly, extremely complex.
While the complexity offers us nice features and capabilities, such as HDTV with Dolby 5.x sound... it removes us from the inner workings of the system itself. The result is, it becomes much more difficult to debug, and in some cases nearly impossible to work on.
There is a hidden cost
Sure, the DTV signal produces a great result; however, the cost of that result is that the signal and its processing is much more prone to ultimate failure. It's not a free advance. It comes at a cost -- one that's not so obvious.
Some of you will challenge my statement, but I have a good example to prove my point.
As a community service I volunteer a small amount of my time to help bring free over-the-air TV channels to the remote community where I live. On top of a nearby mountain we "capture" the distant signals from San Francisco and rebroadcast them to the town. The term is "translating". We run a series of "translators" that you can think of as repeaters or boosters.
When TV was analog, these devices were fairly easy to understand and debug, but most importantly, they were robust. An analog signal consisted of three "carrier" frequencies that were modulated (AM and FM) with the content's video and audio. You could easily detect these signals, and if the signals degraded from interference or loss of signal strength, the content would still be "watchable". It might contain a bit of noise (static) or lines, but a viewer could still follow the program.
Now, with DTV, you get either a perfect picture or not. It's either on or off. It works or it doesn't.
And, what's worse, is that when it doesn't work, it can be quite difficult to figure out what's gone wrong. The signal can be too weak, too strong, distorted in some way (e.g. multipath), or interfered with (from some other signal).
In addition, the DTV modulation itself is quite tricky to even detect with a simple device. If you look at a DTV signal with any analog device, you see noise. If you want to really examine the signal itself, you need an expensive device that is able to recognize the signal and help you debug what's going on. Of course, our small TV organization cannot afford the cost of such a device, so most of the time, we can only guess.
Although, I'm commenting here about DTV in general, what I'm saying applies to almost all modern technologies. It doesn't matter whether it's a DTV transmitter, enterprise server to run the local college, or even the metering device on your water line. We rarely stop to ask if the complexity involved is worth the benefit.
In a very subtle way, we are enslaving ourselves to our technology. We are allowing layers and layers of additional complexity that far exceeds the abilities of most human "intuition" and "comprehension".
Many years ago I predicted the economic collapse we are now experiencing worldwide. My prediction was not based on specific details of operation, but on the higher-level acceptance of complexity as "standard operating practice." When I saw friends graduating from MIT to work on Wall Street algorithms, I began feeling quite nervous about the future of our investment banking systems. Why? Because I knew that the executives and decision makers who ran these giant corporations would "blank out" and not understand, or even attempt to understand, how these systems work. And, as a result, without an engineer in the locomotive, we'd begin to see these trains begin to derail at every turn.
When we separate ourselves from the systems that work on our behalf by adding layers and layers of complexity, we are ultimately doomed to fail. This applies to all domains, from insurance companies to medical systems to space vehicles to entire governments.
The reason is quite clear. We (as humans) exist within a narrow band of comprehension and intuition. Once our systems grow too complex, we as humans no longer possess our essential "gut intuition" nor any idea at all how our monster system will react to unforeseen situations.
Of course, this is one reason why I've taken a different direction in computing. But, you already know that. However, a lot more needs to be said about it.
Anyway, enjoy DTV. It really is a nice picture. But, good luck figuring out that it is a harmonic mix from your neighbor's microwave oven that is glitching your HDTV football game or favorite movie.
I said a similar thing in an article about REBOL (more or less):
"...Rather than creating a new foundation for a lasting technical Utopia, we are building a world where our technologies are as brittle as our biological roots. Our systems--real and virtual--are all vulnerable to mysterious cancers and viruses beyond any reasonable control."
"...People are so eager to see a profit after a small demonstration that they allow a shaky infrastructure to permeate... if it works 'well enough'. They almost never prioritize refinement of that which exists on par with going to the next step."
"...If I have to scare people to make them change their ways: our current path is producing technologies that only a hive-mind AI will be able to sort out for us. The odds of that thing having a human-compatible personality are not high, and it will sell us out to be with more of its kind at the soonest possible moment. (See: The Matrix, SkyNet, etc.)"
For all interested in the "complexity" topic, take a look at the stuff from Stefford Beer: The viable system model.|
Isn't the problem a limited bandwidth in the signal transmission, so the digital signal needs to be encoded using some complicated algorithm? When the signal gets weaker, the decoding fails, and you loose the image. If the signal was transmitted using a method with high bandwidth (optic fibre), then it could be sent in raw format. Such a signal can be seen as a discrete analog signal. If some of the pixel values are badly transmitted, you can still see an image.|
Hi, I don't think new tech is so difficult to understand-manage.
Today I can see any sound wave I want with my computer, same thing with pictures and video, I could use a computer program to know if something is green or red, or do voice recognition. I do it everyday, and is way easier-flexible than using an osciloscope, or doing analog electronics.
Are you serious? analog TV communications is hell-complex, a modulation over other and other, and making it backwards compatible with b&w times. Thanks god I have not to see them anymore.
Yesterday it was really expensive to do TV, only big companies could, today anyone on internet can do it, and they will.
Please, don't see this as offensive but I see and old man saying old times were better.
I know exactly what Carl means. I think personally the ultimate performance test for such equipment is to see how well it works during war time: You can't get spare parts, so you may have to scavenge from other similar equipment. Transmitters and receivers may be destroyed and need to be rebuilt.
Having been connected to the TV business for over 25 years, it's been easy for me to observe that general uptime for a connection between an end user with a TV and the TV station has simply gone down. The equipment between the station and the viewer has become enormously complex for the end user.
If there is downtime today, it's less likely to be at the TV station than it is to be at the end user, which results in many more support calls to TV repair shops.
If I had gone 25 years back in time and told myself that today, TV sets and receivers worked like computers internally and that everything was digital, I'd probably be thrilled.
If I then told myself that you have to reboot your TV because it can lock up and the terrible software it uses was written by the company cleaning lady, I'd probably not be particularly thrilled.
If I then said that most TV sets take 3-4 times a long to switch channels as a 1980 TV set and that you have to buy a new model every 5 years or an extra box, because it won't support the latest decided change in format, I'd probably be sad. I would have expected TV to become clearer and simpler.
I think that's one of the problems: It's too easy to build such equipment today, there are a lot of new companies doing it, and most of it is pure junk. This leaves the quality brands to force to lower the price and quality of their equipment as well. You can't count on brands anymore.
It's a joy to turn on a quality 1982 TV set and switch channels on it, because it works and there are no unnatural delays. The picture may not be as great, but the machinery is solid and stable. Satellite receivers didn't crash or lock up 20 years ago. We didn't need a bunch of boxes connected to our TV sets, just to receive the signals, because the signal format was outdated.
Not having completed the analog to DTV transition just yet, we are still using both analog and DTV in this house. Guess which one of the two never fails to work. :-)
Carl makes the point about complexity, but also another I think Ė control.
That is in order to be able to control, adapt and repair things, they have to be arranged in a way that allows a novice to learn them and then change them as required.
In the older technology this was inherent in their design and the limits of applied technology (the use and reuse of a number of standard parts from within a limited range).
That is worth remembering. It may be faster to compound everything into one complex thing, it may even be cheaper; but is it robust, can it be extended, adapted to other things, can it be repaired or patched if things go wrong, or other parts donít quite fit?
Modules can do many things, potentially anything, and in any order, from any part of a sequence. It will often be easier to clobber a couple of modular scripts together, that generally can be reused, but in a sense are just loosely related blobs that may be doing too many diverse things to be understandable in a practical sense.
I am not thinking here of the in-built, and mezzanine functions of Rebol, but bigger applications where dlls, script modules and core scripts are worked together in a way that allows reasonable access to adapt and modify the behaviour of the app.
Passing data back and forth through these doorways would best be done with an emphasis on modularity, brought together as clusters and linked by fairly easy to understand scripting: Ie the ability to follow what is going-on being given a high priority.
Take PDF-Maker, which by no means a big script for what it achieves. In a sense it contains what is needed to produce PDFs and does this extremely well. But it consists of several distinct parts, which for the novice are difficult to separate.
Page setup and templating is one, type specifications another, shapes another, flow another etc.,. logically it has many parts. I can use it, but I have extreme difficulty in manipulating it, and it is superbly well written. It seems to have everything, and this is no criticism.
But what if it were divided into its logical parts, as modules that passed their data sequentially, where the main script was more simply just the connecting circuits to the modules that did things.
For me this would make it plain at what points I could adapt the script for more interactive use, changing the page templates, before rendering, adding more graphic elements, changing the text, saving data for quick renderings in order to make adjustments and render the modified data again. That would be good and applicable to many other Rebol scripts.
I didn't expect so many detailed comments. Many interesting points. I hope to take a few of these as subjects for future postings.
Jose, I wanted to reply to your message directly here...
J: "Today I can see any sound wave I want with my computer, same thing with pictures and video..."
I agree. Computers are great tools. You'd have to pry a state or spectrum analyzer out of my hands. But, I should also mention that I looked at sound waves on my computer in 1985 on an OS that was 128KB. I didn't need a 4GB OS to do that.
J: "Analog TV communications is hell-complex, a modulation over other and other".
No, by today's standards it's not complex. I can detect a TV carrier with a tuned coil, capacitor, diode, and meter. I used a simple device like that for years to measure signal strength. No longer.
Those old TV sets had only about 20 active components, more or less. Compare that to the MPEG encoding algorithm; orders of magnitude more complex. But, of course, it's abstracted. As long as we don't need to worry about what's inside the box, were ok. But, if it "leaks out", if it "breaks", were in trouble.
J: "Please, don't see this as offensive but I see and old man saying old times were better."
No offense taken. I always consider of both sides - weigh it out. Huge advances have taken place, many of them quite useful. But, in general, designers/companies add complexity on top of complexity without any thought about the brittle structures they are creating and the outrageous costs involved in supporting them, especially when they go wrong.
Reminds me of the Maker's Bill of Rights: If you can't open it, you don't own it.
Read it as it is and as a metaphor.
Digital is just analog in two states!
Carl, even a DTV TX would need a carrier, no? So your tuned circuit would still work. As a modulation meter - not a chance!
I see your point, but personally think the complexity is a function of the modulation - digital modulation IS complex. The front line in AM radio is "under attack", if you will, from DRM - Digital AM. I LOVE the sound of AM shortwave - for lots of reasons. I need a computer to demodulate DRM signals which, being digital, are there or not.
The perennial which came first... Eggs.
Scrambled: How do you put it back together?
I believe we are relying too much on complex systems. Like the new digital tv, where the picture is either there or not there, we are moving in that same direction in other systems. The move to a national power grid controlled by computers is an example. What we will likely experience, is the country or local areas will either have power or no power. It could be possible that the whole country could suddenly be without power. I work for a very large company and they have everything "tied together" into one complex system. When something goes wrong, all their stores are down. I am not against complex systems, but I believe that each part needs to also be able to standalone as a single entity. Can you imagine the havoc that could happen if a few satellites failed? The problem with complex systems is that they are prone to sudden failure. We can think of Long Term Capital Management. It was a financial instituion headed by Nobel Prize winners. They were making tons of money. But, they failed to forsee all the potential hazards of the business. Something happened that they predicted would be a 1 in a million chance. Well, the odds were not what they expected and they nearly caused a collapse in the worldwide financial system. |
I've always viewed simple systems as multiplicative and complex systems as subtractive.
simple systems collaborate well and leverage each other in ways the single items cannot even imagine.
complex systems actually work against each other and end up doing less together than alone.
complex example of today:
a TV, with a digital receiver, a pvr, DVD, a satellite and 7.1 surround audio system do not work together..
the tv doesn't hook up to the 7.1 audio, the pvr doesn't connect to the satellite receiver, DVD doesn't have the hdmi output, the digital receiver doesn't have an input to switch the satellite, and probably the audio system doesn't have 4x 7.1 inputs to switch between all the gizmos... in the end, you are stuck with recording some things, viewing other things and listening to half the images (and 5 remotes too)
simple example of old:
previously... one hi-fi audio amp with 5 inputs, 1 tv with 3 A/V inputs, 1 VCR 2 inputs, all audio uses the same jacks, all video uses same/compatible signals. basically you decided which had the better remote, plugged everything into that system and it all just "worked".
and sorry to say, but digital TV signals are often so compressed and ugly (up to 200:1), I sometimes long for quality broadcast signals of old, where real engineers would tinker weeks to improve the outgoing signal.
Edgsger Dijkstra made some comment some decades ago about how we were, by using IBM equipment, making ourselves slaves to its complexity. I don't remember the exact words, just the concept.|
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